[marmight]

The tearing situation has also recently improved [1,2,3] in X.org, including your cited use case of multiple, rotated monitors, and even if you are not using a compositor, although these improvements are only present in the latest master branch and aren't in any release and thus not shipped by most Linux distributions. I'm sure that the argument could be made about how Wayland still solves the tearing problem more optimally, and I think you should stick with Wayland if you are happy with it, but the tearing situation has improved dramatically on the X side of things since Wayland as well.

[1] https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests...

[2] https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests...

[3] https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests...